Slept through an iPhone alarm last year and missed a flight. Turns out a few obvious settings can silently disable your alarm. Here are the 6 fixes that bring iPhone alarms back to actually waking you up.
Start with the first one. Most alarm issues are caused by it.
Check the alarm volume separately
iPhone has two volume controls – media volume and ringer/alarm volume. The side buttons control whichever you used last. If you turned media volume up but ringer is silent, the alarm plays at zero.
Open Settings then Sounds & Haptics. Look at the Ringer and Alerts slider. Drag it up to a reasonable level. Turn off Change with Buttons below to lock the alarm volume so it doesn't drop accidentally.
Verify the alarm sound isn't set to None
Open the Clock app. Tap Alarms. Tap Edit top-left, then tap your alarm.
Check the Sound option. If it's set to None or Vibration Only, that's the problem. Pick an actual alarm sound from the list. Apple's default options work well – Radar, Apex, or Beacon are loud and recognizable.
Make sure Focus modes aren't silencing alarms
Focus modes like Sleep or Do Not Disturb can silence everything including alarms if you configured them that way. By default, alarms play through Focus modes, but settings can change.
Go to Settings then Focus. Open whatever mode you use overnight (usually Sleep). Check the Allowed Notifications section. Make sure Clock app is allowed or that "Allow Time Sensitive" is on.
Don't use the bedtime/sleep schedule alarm
The Sleep alarm in the Clock app behaves differently than regular alarms. It plays more quietly and stops faster. People often think their alarm broke when really they're using the Sleep schedule one and it's working as designed.
To switch to a regular alarm, tap Alarms tab, then the plus icon to make a new one. This is a standard alarm with full volume and the snooze options you control directly.
Check Bluetooth and audio routing
If your iPhone is paired to a Bluetooth speaker or AirPods, the alarm might play through them instead of the phone speaker. Check Control Center while connected to confirm audio is routing to iPhone.
Actually, this is more common than people realize. Falling asleep with AirPods in the case can leave them paired even when they're in the case. The alarm tries to play through silent headphones.
Turn off Bluetooth before sleep if this happens often. Or disconnect specific devices from the Bluetooth menu before bed.
Restart your iPhone
If you've checked the basics and the alarm still fails, restart the phone. Hold the side button and volume button, slide to power off, wait 10 seconds, then power back on.
This clears stuck audio processes. The alarm should work on the next scheduled time.
Set a backup alarm
This isn't a fix but it's a habit worth having. Set two alarms – one for your wake time, one for 5 minutes after. If the first fails for any reason, the second catches you.
I always do this for early flights. Two alarms, different sounds. One is always working even if I forgot to check settings the night before.
When the alarm goes off but you don't hear it
If the alarm fires but you sleep through it, the issue is volume or sound choice. Use Radar (the default), Apex, or a custom imported song with strong beats. Avoid soft chimes and ambient sounds.
Place the phone across the room. The walk to turn it off forces you out of bed and you're awake by then. Old trick but it works.
Which fix worked or didn't? Tell me in comments and I'll update what's most reliable.